Search

We have created an up-to-date catalogue of 214 brown dwarfs (BDs) in binaries with P < 104 d. This allows us to examine the population statistics of the BD desert. We searched Gaia third data release (DR3) non-single star (NSS) results for orbital inclinations of BD candidates, deriving 12 new masses. Three remain as desert BDs whereas nine candidates are found to be low-mass stars. We improved the radial velocity (RV) solutions for three previously studied BD candidates. A further 19 BD masses with periods less than ∼1200 d were identified in the DR3 binary_masses data base. We confirm a valley in the mass distribution with a minimum around 30–35 Mjup, and find that periods <100 d are still underpopulated in comparison with longer periods. The updated mass and eccentricity distribution of BDs still shows a marginally statistically significant split into high- and low-mass BD populations. This hints at two different parent distributions, and two potential origins – either akin to planetary formation, or stellar. There are no low-eccentricity BDs at periods around 100 d. The mass–metallicity distribution of BDs indicates that core accretion is not the dominant formation mechanism for BDs as they do not follow the same trends that giant exoplanets do with metallicity. We identify a diagonal envelope bounding the Gaia BDs in the mass–period plane due to the detection thresholds of the currently available NSS solutions from 34 months of data. [ABSTRACT FROM AUTHOR]

We present additional HARPS radial velocity observations of the highly eccentric (e ∼ 0.6) binary system DMPP-3AB, which comprises a K0V primary and a low-mass companion at the hydrogen burning limit. The binary has a 507 d orbital period and a 1.2 au semimajor axis. The primary component harbours a known 2.2 M⊕ planet, DMPP-3A b, with a 6.67-d orbit. New HARPS measurements constrain periastron passage for the binary orbit and add further integrity to previously derived solutions for both companion and planet orbits. Gaia astrometry independently confirms the binary orbit and establishes the inclination of the binary is 63.89 ± 0.78°. We performed dynamical simulations that establish that the previously identified ∼800 d RV signal cannot be attributed to an orbiting body. The additional observations, a deviation from strict periodicity, and our new analyses of activity indicators suggest the ∼800 d signal is caused by stellar activity. We conclude that there may be long-period planet 'detections' in other systems, which are similar misinterpreted stellar activity artefacts. Without the unusual eccentric binary companion to the planet-hosting star, we could have accepted the ∼800 d signal as a probable planet. Further monitoring of DMPP-3 will reveal which signatures can be used to most efficiently identify these imposters. We also report a threshold detection (0.2 per cent FAP) of a ∼2.26 d periodicity in the RVs, potentially attributed to an Earth-mass S-type planet interior to DMPP-3A b. [ABSTRACT FROM AUTHOR]

Presents a continuation of lists of selected dissertations begun in the July 1970 issue of the journal "Western Historical Quarterly." "Raised Field Landscapes of Native North America," by William Gustav Gartner; "Carey McWilliams and the Question of Cultural Citizenship in the 1940s," by Maria Jose Canelo; "The Role of Ideology in the Growth, Establishment, and Decline of the Black Panther Party: 1966 to 1982," by Paul Alkebulan.

Presents a list of dissertations about western history. "Mexican Immigrant Family Farms in the California Strawberry Industry," by Teresa Figueroa Sanchez; "The Morning After the Gold Rush: Prentice Mulford and the American Dream," by Enoch Anderson; "Shaping the Shoreline: Environment, Society, and Culture in Monterey, California," by Connie Young Chiang.

Analyzes the potential magnetic field of AB Doradism. Comparison of the Zeeman and Doppler images; Calculation of the azimuthal component of the corresponding potential field; Application of cross-correlation differentiation between potential and observed azimuthal field distributions.

Background At the start of the 2019–2020 influenza season, concern arose that circulating B/Victoria viruses of the globally emerging clade V1A.3 were antigenically drifted from the strain included in the vaccine. Intense B/Victoria activity was followed by circulation of genetically diverse A(H1N1)pdm09 viruses that were also antigenically drifted. We measured vaccine effectiveness (VE) in the United States against illness from these emerging viruses. Methods We enrolled outpatients aged ≥6 months with acute respiratory illness at 5 sites. Respiratory specimens were tested for influenza by reverse-transcriptase polymerase chain reaction (RT-PCR). Using the test-negative design, we determined influenza VE by virus subtype/lineage and genetic subclades by comparing odds of vaccination in influenza cases versus test-negative controls. Results Among 8845 enrollees, 2722 (31%) tested positive for influenza, including 1209 (44%) for B/Victoria and 1405 (51%) for A(H1N1)pdm09. Effectiveness against any influenza illness was 39% (95% confidence interval [CI]: 32–44), 45% (95% CI: 37–52) against B/Victoria and 30% (95% CI: 21–39) against A(H1N1)pdm09-associated illness. Vaccination offered no protection against A(H1N1)pdm09 viruses with antigenically drifted clade 6B.1A 183P-5A+156K HA genes (VE 7%; 95% CI: –14 to 23%) which predominated after January. Conclusions Vaccination provided protection against influenza illness, mainly due to infections from B/Victoria viruses. Vaccine protection against illness from A(H1N1)pdm09 was lower than historically observed effectiveness of 40%–60%, due to late-season vaccine mismatch following emergence of antigenically drifted viruses. The effect of drift on vaccine protection is not easy to predict and, even in drifted years, significant protection can be observed. [ABSTRACT FROM AUTHOR]

Background: Influenza causes significant morbidity and mortality and stresses hospital resources during periods of increased circulation. We evaluated the effectiveness of the 2019-2020 influenza vaccine against influenza-associated hospitalization in the United States.Methods: We included adults hospitalized with acute respiratory illness at 14 hospitals and tested for influenza viruses by reserve-transcription polymerase chain reaction. Vaccine effectiveness (VE) was estimated by comparing the odds of current-season influenza vaccination in test-positive influenza cases vs test-negative controls, adjusting for confounders. VE was stratified by age and major circulating influenza types along with A(H1N1)pdm09 genetic subgroups.Results: A total of 3116 participants were included, including 18% (n = 553) influenza-positive cases. Median age was 63 years. Sixty-seven percent (n = 2079) received vaccination. Overall adjusted VE against influenza viruses was 41% (95% confidence interval [CI], 27%-52%). VE against A(H1N1)pdm09 viruses was 40% (95% CI, 24%-53%) and 33% against B viruses (95% CI, 0-56%). Of the 2 major A(H1N1)pdm09 subgroups (representing 90% of sequenced H1N1 viruses), VE against one group (5A + 187A,189E) was 59% (95% CI, 34%-75%) whereas no VE was observed against the other group (5A + 156K) (-1% [95% CI, -61% to 37%]).Conclusions: In a primarily older population, influenza vaccination was associated with a 41% reduction in risk of hospitalized influenza illness. [ABSTRACT FROM AUTHOR]

A suspected outbreak of influenza A and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at a long-term care facility in Los Angeles County was, months later, determined to not involve influenza. To prevent inadvertent transmission of infections, facilities should use highly specific influenza diagnostics and follow Centers for Disease Control and Prevention (CDC) guidelines that specifically address infection control challenges. [ABSTRACT FROM AUTHOR]

Background: Increased illness due to antigenically drifted A(H3N2) clade 3C.3a influenza viruses prompted concerns about vaccine effectiveness (VE) and vaccine strain selection. We used US virologic surveillance and US Influenza Vaccine Effectiveness (Flu VE) Network data to evaluate consequences of this clade.Methods: Distribution of influenza viruses was described using virologic surveillance data. The Flu VE Network enrolled ambulatory care patients aged ≥6 months with acute respiratory illness at 5 sites. Respiratory specimens were tested for influenza by means of reverse-transcriptase polymerase chain reaction and were sequenced. Using a test-negative design, we estimated VE, comparing the odds of influenza among vaccinated versus unvaccinated participants.Results: During the 2018-2019 influenza season, A(H3N2) clade 3C.3a viruses caused an increasing proportion of influenza cases. Among 2763 Flu VE Network case patients, 1325 (48%) were infected with A(H1N1)pdm09 and 1350 (49%) with A(H3N2); clade 3C.3a accounted for 977 (93%) of 1054 sequenced A(H3N2) viruses. VE was 44% (95% confidence interval, 37%-51%) against A(H1N1)pdm09 and 9% (-4% to 20%) against A(H3N2); VE was 5% (-10% to 19%) against A(H3N2) clade 3C.3a viruses.Conclusions: The predominance of A(H3N2) clade 3C.3a viruses during the latter part of the 2018-2019 season was associated with decreased VE, supporting the A(H3N2) vaccine component update for 2019-2020 northern hemisphere influenza vaccines. [ABSTRACT FROM AUTHOR]

Background During the 2014–2015 US influenza season, 320 cases of non-mumps parotitis (NMP) among residents of 21 states were reported to the Centers for Disease Control and Prevention (CDC). We conducted an epidemiologic and laboratory investigation to determine viral etiologies and clinical features of NMP during this unusually large occurrence. Methods NMP was defined as acute parotitis or other salivary gland swelling of >2 days duration in a person with a mumps- negative laboratory result. Using a standardized questionnaire, we collected demographic and clinical information. Buccal samples were tested at the CDC for selected viruses, including mumps, influenza, human parainfluenza viruses (HPIVs) 1–4, adenoviruses, cytomegalovirus, Epstein-Barr virus (EBV), herpes simplex viruses (HSVs) 1 and 2, and human herpes viruses (HHVs) 6A and 6B. Results Among the 320 patients, 65% were male, median age was 14.5 years (range, 0–90), and 67% reported unilateral parotitis. Commonly reported symptoms included sore throat (55%) and fever (48%). Viruses were detected in 210 (71%) of 294 NMP patients with adequate samples for testing, ≥2 viruses were detected in 37 samples, and 248 total virus detections were made among all samples. These included 156 influenza A(H3N2), 42 HHV6B, 32 EBV, 8 HPIV2, 2 HPIV3, 3 adenovirus, 4 HSV-1, and 1 HSV-2. Influenza A(H3N2), HHV6B, and EBV were the most frequently codetected viruses. Conclusions Our findings suggest that, in addition to mumps, clinicians should consider respiratory viral (influenza) and herpes viral etiologies for parotitis, particularly among patients without epidemiologic links to mumps cases or outbreaks. [ABSTRACT FROM AUTHOR]

Background During the 2014–2015 influenza season in the United States, 256 cases of influenza-associated parotitis were reported from 27 states. We conducted a case-control study and laboratory investigation to further describe this rare clinical manifestation of influenza. Methods During February 2015–April 2015, we interviewed 50 cases (with parotitis) and 124 ill controls (without parotitis) with laboratory-confirmed influenza; participants resided in 11 states and were matched by age, state, hospital admission status, and specimen collection date. Influenza viruses were characterized using real-time polymerase chain reaction and next-generation sequencing. We compared cases and controls using conditional logistic regression. Specimens from additional reported cases were also analyzed. Results Cases, 73% of whom were aged <20 years, experienced painful (86%), unilateral (68%) parotitis a median of 4 (range, 0–16) days after onset of systemic or respiratory symptoms. Cases were more likely than controls to be male (76% vs 51%; P =.005). We detected influenza A(H3N2) viruses, genetic group 3C.2a, in 100% (32/32) of case and 92% (105/108) of control specimens sequenced (P =.22). Influenza B and A(H3N2) 3C.3 and 3C.3b genetic group virus infections were detected in specimens from additional cases. Conclusions Influenza-associated parotitis, as reported here and in prior sporadic case reports, seems to occur primarily with influenza A(H3N2) virus infection. Because of the different clinical and infection control considerations for mumps and influenza virus infections, we recommend clinicians consider influenza in the differential diagnoses among patients with acute parotitis during the influenza season. [ABSTRACT FROM AUTHOR]

Background: During the 2014-2015 US influenza season, expanded genetic characterization of circulating influenza A(H3N2) viruses was used to assess the impact of the genetic variability of influenza A(H3N2) viruses on influenza vaccine effectiveness (VE).Methods: A novel pyrosequencing assay was used to determine genetic group, based on hemagglutinin (HA) gene sequences, of influenza A(H3N2) viruses from patients enrolled at US Influenza Vaccine Effectiveness Network sites. VE was estimated using a test-negative design comparing vaccination among patients infected with influenza A(H3N2) viruses and uninfected patients.Results: Among 9710 enrollees, 1868 (19%) tested positive for influenza A(H3N2) virus; genetic characterization of 1397 viruses showed that 1134 (81%) belonged to 1 HA genetic group (3C.2a) of antigenically drifted influenza A(H3N2) viruses. Effectiveness of 2014-2015 influenza vaccination varied by influenza A(H3N2) virus genetic group from 1% (95% confidence interval [CI], -14% to 14%) against illness caused by antigenically drifted influenza A(H3N2) virus group 3C.2a viruses versus 44% (95% CI, 16%-63%) against illness caused by vaccine-like influenza A(H3N2) virus group 3C.3b viruses.Conclusions: Effectiveness of 2014-2015 influenza vaccination varied by genetic group of influenza A(H3N2) virus. Changes in HA genes related to antigenic drift were associated with reduced VE. [ABSTRACT FROM AUTHOR]